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Homework Help: Quick trigonometry question

  1. Nov 12, 2008 #1
    1. The problem statement, all variables and given/known data
    When dealing with periods and amplitudes in trigonometry, are all complete cycles (for cosine, sine, and tan functions) considered to be 360(degrees)?

    I'm just wondering, because I want to make sure now so that I can apply it to the appropriate questions when the time comes.


    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Nov 13, 2008 #2
    I think this is the right thing for you: http://catcode.com/trig/trig09.html

    Also the period of the trigonometric functions is not same for all of them.

    sin(x) and cos(x) have 2k[itex]\pi[/itex] period and tg(x) and ctg(x) have k[itex]\pi[/itex] period.

    So if you have:
    sinx=a:
    [tex]x=\begin{bmatrix}
    arcsin(a)+2k\pi\\
    \pi - arcsin(a)+2k\pi
    \end{bmatrix}[/tex]
    cosx=a:
    [tex]x=\begin{bmatrix}
    \pm arccos(a)+2k\pi \\
    \end{bmatrix}[/tex]
    tgx=a:
    [tex]x=\begin{bmatrix}
    arctg(a) + k\pi \\
    \end{bmatrix}[/tex]
    ctgx=a
    [tex]x=\begin{bmatrix}
    arcctg(a) + k\pi \\
    \end{bmatrix}[/tex]

    I hope this helped you.
     
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